[en] Because nonlinearity is a frequent occurrence in aerospace applications, there is a need
for e cient analysis procedures. In this context, nonlinear normal modes (NNMs) o er a
solid mathematical tool for interpreting a wide class of nonlinear dynamical phenomena.
The objective of this study is to highlight the usefulness of NNMs for modeling and testing
of nonlinear aerospace structures. Both theoretical and experimental modal analysis are
described and are illustrated.